Motor vehicle body comprising a support structure composed of large-size partial modules

ABSTRACT

The invention relates to a motor vehicle body, the support structure ( 10 ) of which is composed of large-size partial modules ( 12, 34, 50, 66 ), a basic module ( 12 ) comprising lateral longitudinal members ( 15 ) and a body floor ( 14 ) and reaching laterally as far as front wall columns ( 20 ), and, when the support structure ( 10 ) is assembled, the basic module ( 12 ) being connected to a front end module ( 34 ) which belongs to the front crumple zone of the motor vehicle and is supported in a crash stable manner on the basic module ( 12 ).  
     In order to provide a motor vehicle body, in which the front end module ( 34 ) even without a roof construction is fixed in a sufficiently stable manner on the basic module ( 12 ), a front end region ( 36 ) of the body floor ( 14 ) belongs to the front end module ( 34 ) and extends rearward over a considerable length region of the basic module ( 12 ) between lateral longitudinal member sections ( 16 ).

BACKGROUND AND SUMMARY OF THE INVENTION

This invention relates to a motor vehicle body.

A body having a support structure which is composed of essentially fourlarge-size partial modules, is already known from German publication DE198 33 395 A1. One of the partial modules is designed as a basic module,which reaches laterally as far as front wall columns and has laterallongitudinal members and a body floor. When the support structure isassembled, the basic module is connected to a partial module, which isdesigned as a front end module, belongs to the front crumple zone of themotor vehicle, and is supported in a crash stable manner on the basicmodule. By supplementing the basic module and the front end module witha roof module, or by roof sections provided at the front end of thebasic module, a stable connection of the front end module to the basicmodule is produced.

This invention has as one object the object of providing a motor vehiclebody, in which the front end module is fixed in a sufficiently stablemanner to the basic module even without a roof construction.

This object is achieved according to the invention by the claimedfeatures.

Advantageous refinements of the invention are apparent from thedependent claims.

In body support structure according to the invention, a front end regionof the body floor belongs to the front end module, which region extendsrearward over a considerable length region of the basic module betweenlateral longitudinal member sections. This provides a particularlystable support of the front end module on the basic module of thesupport structure, so that, for example in the case of a head-on crash,a desired deformation sequence is achieved, in which the front endstructure acts in a particularly effective manner as an energy-absorbingcrumple zone and the shape of the passenger safety cell together withthe floor is maintained to the greatest possible extent. The very stablefastening of the front end module to the basic module enables thesupport structure to be used for vehicles of different construction,since the front end module is fastened in a sufficiently stable mannerto the basic module even without a roof construction. This also rendersthe support structure particularly suitable for open motor vehicles.

A particularly stiff and stable connection of the front end module tothe basic module is provided if the front end module has longitudinalmember sections which laterally bound the front end region of the bodyfloor and are to be connected to the lateral longitudinal membersections of the basic module. In this case, the connection between thefront end module and basic module is particularly stable if the mutuallyassigned, lateral longitudinal member sections of the front end moduleand of the basic module are connected to each other via joining surfacesmatched to one another, the joining surfaces extending over the at leastapproximately entire overlapping length of the mutually assignedlongitudinal member sections or of the two modules.

The stability of the connection of the front end module to the basicmodule is further assisted by the lateral longitudinal member sectionsof the front end module and of the basic module each having a boxprofile which is closed in cross section. After the longitudinal membersections which are assigned to one another in each case are joinedtogether, lateral longitudinal members which have a box profile, whichis doubled in cross section, and are particularly stiff are thereforeprovided.

If upwardly protruding column sections are arranged at the front ends ofthe lateral longitudinal member sections of the basic body, then thefront end module and the basic module can also be connected to eachother in the vertical direction, and a stable fastening of the twomodules arises overall. In this case, the upwardly protruding columnsections preferably extend approximately at right angles to thedirection of extent of the longitudinal members.

In a further refinement of the invention, the front end module alsocomprises upwardly protruding column sections which are fastened to thelateral longitudinal member sections thereof. This enables the mutuallyassigned, upwardly protruding column sections of the front end moduleand of the basic module to be connected to each other via joiningsurfaces, which are matched in each case to each other, to form frontdoor columns, so that, on the one hand, a particularly good connectionof the front end module to the basic module is produced and, on theother hand, stiff and stable door columns are provided-preferably up tothe level of the side wall edge of the support structure. A front endwall which stiffens the door columns in the transverse direction of thevehicle preferably extends between the door columns.

The upwardly protruding column sections of the front end module and ofthe basic module preferably each comprise a box profile which is closedin cross section, so that, after the column sections which are assignedto one another laterally in each case are joined together, particularlystiff door columns with a box profile which is doubled in cross sectionare provided.

After the large-size partial modules have been assembled, the supportstructure is to be lined with outer panel parts which cover the joiningpoints of the partial modules with the outer panel parts. This ensuresthat, on the one hand, the partial modules can be joined with sufficienttolerances in a simple manner in terms of manufacturing and thereforecost-effectively and, on the other hand, that the joining points arecovered, giving an impression of high quality.

Further advantages, features and details of the invention emerge fromthe description below of a preferred exemplary embodiment and withreference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded illustration of the support structureof the motor vehicle body according to the invention, which supportstructure is assembled from large-size partial modules;

FIG. 2 shows a further perspective exploded illustration of the supportstructure which is assembled from partial modules and is lined withouter panel parts;

FIG. 3 shows a perspective view of a partial module of the supportstructure designed as a front end module;

FIG. 4 shows a perspective view of a partial module of the supportstructure designed as a basic module;

FIGS. 5 a and 5 b each show partial perspective views of the basicmodule and the front end module before they have been joined together;

FIG. 6 shows a perspective view of the basic module and of the front endmodule after they have been joined together;

FIG. 7 shows a perspective view of a partial module of the supportstructure designed as a rear module;

FIG. 8 shows a perspective view of a partial module of the supportstructure designed as a roof module; and

FIG. 9 shows a partial perspective view of the assembled supportstructure which in each case comprises a left and a right side wallmodule.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows, in a perspective exploded illustration, a supportstructure 10 of a motor vehicle body that is assembled from a pluralityof large-size partial modules which are described in more detail below.In the exemplary embodiment shown here, the partial modules of thesupport structure 10 are produced in each case from a plurality ofsheet-metal parts joined together; at the same time, however, thepartial modules may also be premanufactured in different constructions,for example as a “space frame”, as plastic parts, metal cast parts, ascomponents in a “sandwich construction” or the like. In particular,combinations of different constructions are also conceivable here forthe joined together partial modules, depending on application andloading. The individual modules are joined together in particular viabonding connections, welding connections or the like. At the same time,other customary connections, such as screw connections or the like, areconceivable.

A basic module 12 of the support structure 10, which basic module can beseen in an overall view of FIG. 1 and in FIG. 4, essentially comprises abody floor 14 which is bounded laterally by longitudinal members 15. Thebasic module 12 reaches forward with longitudinal member sections 16 asfar as column sections 18 of front wall columns 20 which protrude upwardfrom the respectively assigned, front ends of the lateral longitudinalmember sections 16. The body floor 14 of the basic module 12 ends at aconsiderable distance behind the front end of the basic module 12 orbehind the column sections 18 of the front wall columns 20. In thiscase, the body floor 14 is provided here with a central tunnel 22 andwith crossmembers 24 which extend outward from said tunnel and areconnected fixedly to the longitudinal members 15. At the rear, the basicmodule 12 ends behind rear wheel houses 26, to the inside of whichextensions 28 of the lateral longitudinal members 15 extend. Above therear wheel houses 26, wall regions 30 of the particular, rear side wallare arranged. The body floor 14 ends at the rear at a crossmember 32which extends between the extensions 28 of the lateral longitudinalmembers 15 in the transverse direction of the vehicle level with therear wheel houses 26. The basic module 12 is already equipped as far aspossible with the other partial modules before the joining together.Thus, for example, the inner lining, possibly the seat system, theelectric and electronic device, or the underfloor system, e.g. withparts of the exhaust system, are already attached to the basic moduleand provided, if appropriate, with adapters, plug-in connections or thelike which permit a connection to further components.

A front end module 34, which can be seen in an overall view in FIG. 3,belongs to the front crumple zone of the motor vehicle and is supportedon the basic module 12 in a crash stable manner is connected to thebasic module 12. For this purpose, the front end module 34 comprises afront end region 36 of the body floor 14 which extends between laterallongitudinal member sections 38 of the front end module 34. As can beseen from the views of FIGS. 3, 5 a and 5 b, the front end region 36 ofthe body floor 14 and the lateral longitudinal member sections 38 end atleast approximately level at the rear. At the front, the front endregion 36 of the body floor 14 ends at a front end wall 40 of thepassenger cell, extending from the front end region 36 of the body floor14 as far as approximately level with the side wall edge of the supportstructure 10. The end wall 40 is bounded laterally by column sections 42of the front wall columns 20 which protrude upward from the laterallongitudinal member sections 38 of the front end module 34. Frontlongitudinal members 44 and front side wall regions 46 can be seen atthe front end of the front end module 34, between which members andregions parts 48 of the wheel house lining of the front wheel houses arearranged. At the front, the front end module 34 is adjoined by a frontmodule 35, part of which is illustrated in FIG. 2. This front module 35comprises, for example, the front bumper, the nose region of the motorvehicle, the headlamps, parts of the radiator and parts of the wheelhouse lining. Like the basic module 12, the front end module 34 is alsoalready equipped as far as possible with the other partial modulesbefore joining together. Thus, in particular, components and assemblies(not shown), such as the instrument panel, the air conditioning system,the pedal system etc, can already be attached to the front end module.

A roof module 50, which can be seen in the overall view of FIG. 9, canbe placed onto the basic module 12 and the front end module 34 and herecomprises lateral A-columns 54, lateral roof columns 56 in the region ofthe roof 52, and C-columns 58. The lower ends of the A-columns 54 and ofthe C-columns 58 are connected to one another via a respectivecrossmember element 60. When the support structure 10 is assembled, theA-columns 54 are supported both on the basic module 12 and on the frontend module 34. In other words, the A-columns 54 are supported at theirlower ends both on the upwardly protruding column sections 18 and 42 ofthe basic module 12 and of the front end module 34, which form theparticular front wall column 20. At the rear, joining surfaces 62 of thelower ends of the C-columns 58 are fastened with joining surfaces 64 tothe respectively assigned, upper end of the wall regions 30, for exampleby means of a bonding connection.

At the rear, the basic module 12 is adjoined by a rear module 66, whichcan be seen in the overall view of FIG. 7 and which, when the supportstructure 10 is assembled together with the rear end region of the basicmodule 12, belongs to the rear crumple zone of the motor vehicle andessentially comprises lateral, rear longitudinal member sections 68, arear crossmember 70 connecting the longitudinal member sections 68 andrear side wall regions 72. When the support structure is assembled, thecrossmember 32 and the longitudinal member extensions 28 of the basicmodule 12 and the longitudinal member sections 68 and the rearcrossmember 70 of the rear module 66 form a supporting frame withinwhich a spare wheel trough (not shown) can be fixed. It is apparent thatthe rear module 66 is connected to the basic module 12 and the roofmodule 50 along a transverse plane of the vehicle that runs vertically.The rear module 66 is fastened to the basic module 12 and the roofmodule 50 via flanges 74 on the longitudinal member extensions 28 or onthe associated longitudinal member sections 68, and via further joiningpoints (not shown) between the modules 12, 50 and 66. To the rear, therear module 66 is adjoined by a rear end module 76, part of which can beseen in FIG. 2. This rear end module 76 comprises, for example, the rearbumper or the rear lighting of the motor vehicle. It is to be regardedas a matter of course that both the roof module 50 and the rear module66 can already be equipped as far as possible with linings, assembliesand components before the support structure 10 is joined together.

In the case of the five-door motor vehicle shown here, a respectivelyassigned B-column 78 is fastened between the lateral roof column 56 ofthe roof module 50 and the lateral longitudinal member 15 of the basicmodule 12.

FIG. 2 illustrates, in a further perspective exploded illustration, thesupport structure 10 which is made of the partial modules 12, 34, 50, 66and is lined with outer panel parts of plaster, sheet metal or the like.Front wing linings 80, in particular, are thus designed in such a mannerthat the joining point 81 between the upwardly protruding columnsections 18 and 42 of the basic module 12 and of the front end module 34is covered and cannot be seen from the outside. In addition, the frontwing linings 80 likewise cover the fastening points of the A-columns 54of the roof module 50 to the basic module 12 and the front end module 34and those fastenings points cannot be seen. Lateral sill linings 82 aredesigned in such a manner that the joining point 83 between therespective longitudinal member sections 16 of the basic module 12 andthe longitudinal member sections 38 of the front end module 34 iscovered in a manner such that it cannot be seen from the outside. Rearwing linings 84 are likewise designed in such a manner that the joiningsurfaces 62, 64 between the C-column 58 and the rear wall region 30 arelikewise covered in a manner such that they cannot be seen from theoutside. It is apparent that all of the joining points of the large-sizepartial modules 12, 34, 50 and 66 are therefore covered by the liningparts 80, 82, 84 and cannot be seen from the outside. This ensures thatthe partial modules can be joined with sufficient tolerances in a simplemanner in terms of manufacturing and therefore cost-effectively and, onthe other hand, the covering of the joining points conveys an impressionof high quality.

The A-columns 54, the lateral roof columns 56 and the C-columns 58 arelined with column lining parts 86, 88.

FIGS. 5 a and 5 b illustrate, in partial perspective views, the joiningtogether of the basic module 12 and of the front end module 34, and FIG.6 illustrates, in a perspective view, the basic module 12 and the frontend module 34 after they have been joined together. It can be seen thatthe front end region 36 of the body floor 14, which region belongs tothe front end module 34, extends rearward over a considerable lengthregion of the basic module 12 between the lateral longitudinal membersections 16. It can furthermore be seen that the mutually assigned,lateral longitudinal member sections 16, 38 of the front end module 34and of the basic module 12 have joining surfaces 83 a, b, which arematched to each other, at the particular joining point 83 (FIG. 2),which joining surfaces extend over the at least approximately entireoverlapping length of the mutually assigned longitudinal member sections16, 38. In this case, the length of the joining surfaces 83 a, bcorresponds approximately to the length of the adjacent, front endregion 36 of the body floor 14. The lateral longitudinal member sections16, 38 of the front end module 34 and of the basic module 12 have arespective box profile which is closed in cross section, so that, afterthe longitudinal member sections 16, 38 which are assigned to each otherin each case have been joined together, lateral longitudinal membershaving a box profile which is doubled in cross section and isapproximately 8-shaped are produced. The box profile of the laterallongitudinal member sections 16, 38 of the front end module 34 and ofthe basic module 12 in each case has a cross section which can be variedover its length and here is stepped. Of course, it would also beconceivable in this connection for the longitudinal member sections 16,38 to each be designed as a partial shell which are then connected toone another to form a support.

The upwardly protruding column sections 18, 42 of the basic module 12and of the front end module 34 comprise joining surfaces 81 a, b, whichare matched in each case to each other, at the particular joining point81 (FIG. 2), via which the column sections 18, 42 are connected to formthe front wall column 20. The upwardly protruding column sections 18, 42in each case comprise a box profile which is closed in cross section, sothat after the respectively assigned column sections 18, 42 have beenjoined together, particularly stiff door columns 20 having a boxprofile, which is doubled in cross section and is approximately8-shaped, are created. The joining surfaces 81 a, b of the columnsections 18, 42 and the joining surfaces 83 a, b of the longitudinalmember sections 16, 38 run here at least approximately at right anglesto one another. The angular bonding of the column sections 18 to thelongitudinal member sections 16 of the basic module 12 or the angularbonding of the column sections 42 to the longitudinal member sections 38of the front end module 34 provides a particularly stiff supporting ofthe front end module 34 on the basic module 12. The position of thebasic module 12 and of the front end module 34 is therefore determinedin the longitudinal direction of the vehicle and in the verticaldirection of the vehicle by the joining surfaces 83 a, b and 81 a, b. Inthe transverse direction of the vehicle, the position of the basicmodule 12 and of the front end module 34 is not determined by thejoining surfaces 83 a, b and 81 a, b but rather, for example, by bearingsurfaces of the basic module 12 and of the front end module 34 in theregion of the central tunnel 22. The front end region 36 of the bodyfloor 14, which end region belongs to the front end module, is connectedin an overlapping manner to that region of the body floor 14 whichbelongs to the basic module 12, as is apparent in particular from FIG.6. In this case, the central tunnel 22 is molded both into the front endregion 36 and into the body floor 14 and is provided with joiningsurfaces.

Finally, FIG. 9 shows, in a partial perspective view, the assembledsupport structure 10 which comprises in each case a left and right sidewall module 100, which extends from behind the front side doors as faras rear door pillars. The side wall module 100 is fastened to the basicmodule 12 above the assigned longitudinal member 15 and opposite therear side wall 30. In addition, the side wall module 100 is supported inrelation to a crossmember 104 by a supporting arrangement 102 in thetransverse direction of the vehicle.

The basic module 12 and the side wall module 100 end level with a commonjoining surface 106 on which a different coupé roof module 50′ here isfixed with a side wall region 108.

1-18. (canceled)
 19. A motor vehicle body having support structure whichis composed of large-size partial modules comprising: a basic modulehaving lateral longitudinal members and a body floor, and reachinglaterally as far as front wall columns; and a front end module formingat least part of a front crumple zone of the motor vehicle and supportedin a crash stable manner on the basic module when the support structureis assembled; wherein a front end region of the body floor belongs tothe front end module and extends rearward over a considerable lengthregion of the basic module between lateral longitudinal member sections.20. The body as claimed in claim 19, wherein the front end modulecomprises longitudinal member sections which laterally bound the frontend region of the body floor and can be connected to the laterallongitudinal member sections of the basic module.
 21. The body asclaimed in claim 20, wherein the longitudinal member sections includemutually assigned, lateral longitudinal member sections of the front endmodule and of the basic module which have joining surfaces that arematched to each other and extend over at least approximately an entireoverlapping length of the mutually assigned longitudinal membersections.
 22. The body as claimed in claim 21, wherein the length of thejoining surfaces corresponds approximately to the length of an adjacent,front end region of the body floor.
 23. The body according to claim 20,wherein the longitudinal member sections of the front end module and thefront end region of the body floor extend rearward to approximately thesame distance.
 24. The body as claimed in claim 20, wherein each of thelongitudinal member sections of the front end module and of the basicmodule has a box profile which is closed in cross section.
 25. The bodyas claimed in claim 24, wherein each of the box profiles of thelongitudinal member sections of the front end module and of the basicmodule has a cross section which can be varied over its length.
 26. Thebody as claimed in claim 19, wherein upwardly protruding column sectionswhich can be connected to the front end module are arranged at the frontends of the lateral longitudinal member sections of the basic module.27. The body as claimed in claim 21, wherein upwardly protruding columnsections between which a front end wall is fastened are arranged on thelateral longitudinal member sections of the front end module.
 28. Thebody as claimed in claim 19, wherein upwardly protruding column sectionsof the front end module and of the basic module can be connected to eachother via joining surfaces, which are matched in each case to eachother, to form front wall columns.
 29. The body as claimed in claim 19,wherein upwardly protruding column sections of the front end module andof the basic module each have a box profile which is closed in crosssection, and extend to approximately level with the side wall edge ofthe support structure.
 30. The body as claimed in claim 19, wherein thefront end region of the vehicle body floor which belongs to the frontend module is connected in an overlapping manner to a region of the bodyfloor which belongs to the basic module.
 31. The body as claimed inclaim 19, wherein the basic module ends behind rear wheel houses and canbe connected to a rear module which, when the support structure isassembled together with the rear end region of the basic module, belongsto a rear crumple zone of the motor vehicle.
 32. The body as claimed inclaim 19, wherein a roof module can be placed onto the basic module andthe front end module, and wherein front roof columns of the roof modulecan be supported both on the basic module and on the front end module.33. The body as claimed in claim 32, wherein the roof module comprises acrossmember which runs below a windshield and via which front wallcolumns are connected to each other.
 34. The body as claimed in claim32, wherein a B-column can be fastened between the roof module and thebasic module.
 35. The body as claimed in claim 19, wherein a side wallmodule can be fastened in each case to the basic module above eachlongitudinal member and extends from behind a front side door as far asa rear door column.
 36. The body as claimed in claim 19, wherein thesupport structure is to be lined with outer panel parts, and whereinjoining points of the partial modules are to be covered by the outerpanel parts.